Simplify the following expression: $x = \dfrac{n^2 + 12n + 20}{n + 2} $
Explanation: First factor the polynomial in the numerator. $ n^2 + 12n + 20 = (n + 2)(n + 10) $ So we can rewrite the expression as: $x = \dfrac{(n + 2)(n + 10)}{n + 2} $ We can divide the numerator and denominator by $(n + 2)$ on condition that $n \neq -2$ Therefore $x = n + 10; n \neq -2$